The boring machines currently used comprise a piece-holding spindle, a tailstock, one or more tools.
The piece to be worked is positioned on the piece-holding spindle and locked onto it. The piece-holding spindle is set rotating and the tool is guided on the surface of the piece to be worked, in such a way as to shape it.
The boring machines used at present have a series of drawbacks:                they do not allow part of the outer surface of complex pieces to be worked, due to the fact that it is difficult for the tool to reach some areas of the object;        they do not allow complex or asymmetrical parts to be worked, since the unbalance of the mass of the object to be processed set rotating causes the oscillation of the piece-holding spindle and of the tailstock, which results in the imprecise working of its surface;        some time is necessary to accurately position the piece to be worked.        
These problems arise in particular in the production of door handles, especially when it is necessary to bore the end of the handle that will be connected to the door.
In fact, both the surface decorative working and the carrying out of precise grooves at the connection end of the handles are particularly difficult due to the presence and to the mass of the handle grip.
To overcome all the drawbacks described above a new boring unit for complex parts, in particular for door handles, with differential control systems has been designed and implemented.
The main aim of the new boring unit is to allow the working of one end of eccentric or asymmetrical parts.
Another aim of the new boring unit is to allow the boring of the connection end of handles.
A further aim of the new boring unit is to ensure the rapid and correct positioning of each piece to be bored.
A further aim of the new boring unit is to ensure the boring of any piece, symmetrical or asymmetrical, with no need to rotate it.
Another aim of the new boring unit is to allow the tools to be rotated on the object to be bored.